Metabolic Epidemiology Branch, Division of Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA.
Center for Cancer Control & Information Services, National Cancer Center, Tokyo, Japan.
Int J Epidemiol. 2022 Aug 10;51(4):1276-1290. doi: 10.1093/ije/dyab224.
Increasing proportions of smokers in Japan smoke <10 cigarettes per day (CPD). Yet, the health risks of low-intensity smoking in Asia are poorly understood.
We performed a pooled analysis of 410 294 adults from nine population-based prospective cohort studies participating in the Japan Cohort Consortium. Cigarette-use data were collected at each study baseline in 1983-1994. Study-specific hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause and cause-specific mortality were calculated using multivariable-adjusted Cox regression by CPD among current smokers and by age at cessation among former smokers, with never smokers as the referent group. Pooled HRs and CIs were computed using a random-effect model.
The smoking prevalence was 54.5% in men and 7.4% in women. About 15.5% of male and 50.4% of female current smokers smoked 1-10 CPD (low-intensity). Both male and female low-intensity smokers had higher all-cause mortality risks than never smokers. Risks were further higher with increasing CPD in a dose-response manner. HRs (95% CIs) were 1.27 (0.97-1.66), 1.45 (1.33-1.59) and 1.49 (1.38-1.62) for 1-2, 3-5 and 6-10 CPD, respectively, in men; 1.28 (1.01-1.62), 1.49 (1.34-1.66) and 1.68 (1.55-1.81) for 1-2, 3-5 and 6-10 CPD, respectively, in women. Similar associations were observed for smoking-related causes of death. Among former low-intensity smokers, younger age at cessation was associated with lower mortality risk.
Smoking very low amounts was associated with increased mortality risks in Japan. All smokers should quit, even if they smoke very few CPD.
在日本，越来越多的吸烟者每天吸烟量不足 10 支（CPD）。然而，亚洲地区低强度吸烟的健康风险尚未得到充分了解。
我们对参加日本队列联盟的九个基于人群的前瞻性队列研究中的 410294 名成年人进行了汇总分析。在 1983-1994 年的每个研究基线收集了吸烟数据。使用多变量调整的 Cox 回归，根据当前吸烟者的 CPD 和以前吸烟者的戒烟年龄，计算了全因和死因特异性死亡率的研究特异性风险比（HRs）和 95%置信区间（CIs），从不吸烟者作为参照组。使用随机效应模型计算汇总的 HR 和 CI。
男性的吸烟率为 54.5%，女性为 7.4%。约 15.5%的男性当前吸烟者和 50.4%的女性当前吸烟者吸烟量为 1-10CPD（低强度）。与从不吸烟者相比，男性和女性低强度吸烟者的全因死亡率风险均更高。随着 CPD 的增加，呈剂量反应关系，风险进一步升高。男性的 HR（95%CI）分别为 1.27（0.97-1.66）、1.45（1.33-1.59）和 1.49（1.38-1.62），CPD 分别为 1-2、3-5 和 6-10；女性分别为 1.28（1.01-1.62）、1.49（1.34-1.66）和 1.68（1.55-1.81），CPD 分别为 1-2、3-5 和 6-10。吸烟相关死因也观察到类似的关联。在以前的低强度吸烟者中，戒烟年龄越小，死亡率风险越低。
在日本，极低量吸烟与死亡率风险增加有关。所有吸烟者都应该戒烟，即使他们吸烟量很少。
